ENSO Updates (2007 thru 2023)

[Blown Away]

Where can I find a list of years with Modoki El Nino?

[Ntxw]

Where can I find a list of years with Modoki El Nino?

In general most weak and/or low end moderate El Ninos are modoki at some point during their tenure. There are a few exceptions such as 2006.

[cycloneye]

:uarrow: They keep showing those warm subsurface waters close to Nino 1+2, I don't think those are going to surface with strong trade winds continuing in that area, IMO.

The strong trade winds are temporary, they'll die down in a day or so and the waters will likely warm precipitously thereafter

http://www.atmos.albany.edu/student/ven ... .5S-5N.gif

And on Q,the four areas are warming.

[Macrocane]

Where can I find a list of years with Modoki El Nino?

According to wikipedia

Recent Central Pacific El Niños happened in 1986–87, 1991–92, 1994–95, 2002–03, 2004–05 and 2009–10. Furthermore, there were "Modoki" events in 1957–59, 1963–64, 1965–66, 1968–70, 1977–78 and 1979–80.

https://en.wikipedia.org/wiki/El_Ni%C3%B1o

[jconsor]

Where can I find a list of years with Modoki El Nino?

Here are two sites with monthly Modoki index values.

http://www.jamstec.go.jp/frsgc/research ... onthly.txt (1870-present)
http://www.wxmidwest.com/emi/newemi.txt (1948-2013)

Generally, Modoki years would be ones where for several months in a row, the JMA Modoki index exceeds 0.5 and the WXMidwest Modoki index exceeds 0.75.
Since 1950, the Modoki Ninos that took place during Atlantic hurricane season were: 1966, 1991, 1994, 2002, 2004

[LarryWx]

:uarrow: Note that despite the 0.2 warming in Niño 3.4, the upper OHC actually cooled a bit to +0.82 after having been near +1.0 in late May. So, perhaps that means any further warming over the next couple of months will be slow overall. I’m still thinking only warm neutral for ASO based largely on the warm biased May Eurosip’s only warm neutral ASO forecast followed by warming to weak to low end moderate El Niño later in fall to winter.

I would hardly call this a substantial drop, nor would I argue we even reached +1.0 in late May, the value was closer to +0.9 than +1.0. I wouldn't over analyze every increase or fall over a 2-3 week period in upper oceanic heat content & assume it will make a huge difference in the long run, especially one this small. If this crash were to be sustained for several weeks then it would certainly make a significant difference, but remember that ENSO evolves slowly over periods of several months or more, I doubt this will really mean anything unless OHC continues to come down for another 3-4 weeks (at least). We also had more WWBs recently so it's bound to stabilize or increase again. The ocean which carries "ENSO" memory between its respective phases, evolves much more slowly than the overlying atmosphere, and it usually takes weeks for a change in atmospheric surface winds due to sub-seasonal forcing (the MJO & CCKW) to reflect onto the ocean in the large-scale. Also keep in mind the Eq Pacific still has a lot of room to play catch up the next few months and the downwelling Kelvin Wave is just now reaching the eastern boundary region (South America) and will soon refract against it, spreading anomalously warm water westward in the process (in the form of slower moving Rossby Waves).

Eric,
I agree that I would hardly call it a substantial drop and I didn't. I said "cooled a bit", meaning a small amount, rather than "substantial drop". Also, the OHC graph within the 6/4/18 report did actually show near +1.0 as per this post:
viewtopic.php?f=31&t=92137&start=9520#p2679283

CPC has since cooled it back some for that period in each of the subsequent two weekly releases, but it was showing near +1.0 then.

Regardless of semantics and exactly how much it has cooled back, it has cooled a small amount and I'm sticking with my prediction that the ASO trimonth will be warm neutral (cooler than +0.5) based largely on the May Eurosip being only warm neutral for ASO. During 2005-17 it never missed a category to the cool side. The average miss was a whopping +0.5, a very significant warm bias. I'm expecting ONI based El Nino to start during the SON trimonth or later.

What are you predicting for the ASO trimonth for Nino 3.4?

Regardless of my prediction of only warm neutral for ASO, I still expect the tropics to be affected negatively by the anticipated oncoming El Nino, which is reflected in my prediction made for the S2K contest.

[Eric Webb]

:uarrow: Note that despite the 0.2 warming in Niño 3.4, the upper OHC actually cooled a bit to +0.82 after having been near +1.0 in late May. So, perhaps that means any further warming over the next couple of months will be slow overall. I’m still thinking only warm neutral for ASO based largely on the warm biased May Eurosip’s only warm neutral ASO forecast followed by warming to weak to low end moderate El Niño later in fall to winter.

I would hardly call this a substantial drop, nor would I argue we even reached +1.0 in late May, the value was closer to +0.9 than +1.0. I wouldn't over analyze every increase or fall over a 2-3 week period in upper oceanic heat content & assume it will make a huge difference in the long run, especially one this small. If this crash were to be sustained for several weeks then it would certainly make a significant difference, but remember that ENSO evolves slowly over periods of several months or more, I doubt this will really mean anything unless OHC continues to come down for another 3-4 weeks (at least). We also had more WWBs recently so it's bound to stabilize or increase again. The ocean which carries "ENSO" memory between its respective phases, evolves much more slowly than the overlying atmosphere, and it usually takes weeks for a change in atmospheric surface winds due to sub-seasonal forcing (the MJO & CCKW) to reflect onto the ocean in the large-scale. Also keep in mind the Eq Pacific still has a lot of room to play catch up the next few months and the downwelling Kelvin Wave is just now reaching the eastern boundary region (South America) and will soon refract against it, spreading anomalously warm water westward in the process (in the form of slower moving Rossby Waves).

http://www.cpc.ncep.noaa.gov/products/a ... t-year.gif

Eric,
I agree that I would hardly call it a substantial drop and I didn't. I said "cooled a bit", meaning a small amount, rather than "substantial drop". Also, the OHC graph within the 6/4/18 report did actually show near +1.0 as per this post:
viewtopic.php?f=31&t=92137&start=9520#p2679283

CPC has since cooled it back some for that period in each of the subsequent two weekly releases, but it was showing near +1.0 then.

Regardless of semantics and exactly how much it has cooled back, it has cooled a small amount and I'm sticking with my prediction that the ASO trimonth will be warm neutral (cooler than +0.5) based largely on the May Eurosip being only warm neutral for ASO. During 2005-17 it never missed a category to the cool side. The average miss was a whopping +0.5, a very significant warm bias. I'm expecting ONI based El Nino to start during the SON trimonth or later.

What are you predicting for the ASO trimonth for Nino 3.4?

Regardless of my prediction of only warm neutral for ASO, I still expect the tropics to be affected negatively by the anticipated oncoming El Nino, which is reflected in my prediction made for the S2K contest.

You're overreacting to what's likely a very small subseasonal, or potentially unmeasurable change in the large-scale Equatorial Pacific. Also remember that the ocean is much slower to respond to the atmosphere, the supposed, apparent cooling in OHC of late is almost assuredly tied to the anomalously strong trade winds in advance of an MJO pulse that's now closing in on the Western Hemisphere, they will probably reverse and increase again because we had a fairly substantial westerly wind burst this past week, you probably won't see those changes due to this aforementioned WWB for a few or even several weeks because of the long adjustment time of the ocean.

There's also an implied, inherent error bar in the CPC's GODAS model that's used in those analyses, they differ substantially depending on the amount of data that's ingested, where the data is sampled, the model used to infill the rest of the analysis, and the resolution and data assimilation techniques for said model in addition to errors attributable to the observations themselves. A change of 0.15-0.2C in upper ocean heat content is essentially noise and shouldn't be interpreted as a significant drop that means anything in the grand scheme of things (like it will somehow stifle this event from becoming a NINO as early as ASO, especially when it occurs over a window that's comparably small vs ENSO) or even much of a drop at all.

Note the discrepancies in all the models below in their analysis of the downwelling Kelvin Wave that's crossing the Eq Pacific, do you really believe with much confidence they can detect a change of less than 0.2C in upper ocean heat content? I think not.

[Kingarabian]

CDAS SST anomalies have been wild as of late. Nino 4 just jumped above +0.5C

[Eric Webb]

:uarrow: Note that despite the 0.2 warming in Niño 3.4, the upper OHC actually cooled a bit to +0.82 after having been near +1.0 in late May. So, perhaps that means any further warming over the next couple of months will be slow overall. I’m still thinking only warm neutral for ASO based largely on the warm biased May Eurosip’s only warm neutral ASO forecast followed by warming to weak to low end moderate El Niño later in fall to winter.

I would hardly call this a substantial drop, nor would I argue we even reached +1.0 in late May, the value was closer to +0.9 than +1.0. I wouldn't over analyze every increase or fall over a 2-3 week period in upper oceanic heat content & assume it will make a huge difference in the long run, especially one this small. If this crash were to be sustained for several weeks then it would certainly make a significant difference, but remember that ENSO evolves slowly over periods of several months or more, I doubt this will really mean anything unless OHC continues to come down for another 3-4 weeks (at least). We also had more WWBs recently so it's bound to stabilize or increase again. The ocean which carries "ENSO" memory between its respective phases, evolves much more slowly than the overlying atmosphere, and it usually takes weeks for a change in atmospheric surface winds due to sub-seasonal forcing (the MJO & CCKW) to reflect onto the ocean in the large-scale. Also keep in mind the Eq Pacific still has a lot of room to play catch up the next few months and the downwelling Kelvin Wave is just now reaching the eastern boundary region (South America) and will soon refract against it, spreading anomalously warm water westward in the process (in the form of slower moving Rossby Waves).

Eric,
I agree that I would hardly call it a substantial drop and I didn't. I said "cooled a bit", meaning a small amount, rather than "substantial drop". Also, the OHC graph within the 6/4/18 report did actually show near +1.0 as per this post:
viewtopic.php?f=31&t=92137&start=9520#p2679283

CPC has since cooled it back some for that period in each of the subsequent two weekly releases, but it was showing near +1.0 then.

Regardless of semantics and exactly how much it has cooled back, it has cooled a small amount and I'm sticking with my prediction that the ASO trimonth will be warm neutral (cooler than +0.5) based largely on the May Eurosip being only warm neutral for ASO. During 2005-17 it never missed a category to the cool side. The average miss was a whopping +0.5, a very significant warm bias. I'm expecting ONI based El Nino to start during the SON trimonth or later.

What are you predicting for the ASO trimonth for Nino 3.4?

Regardless of my prediction of only warm neutral for ASO, I still expect the tropics to be affected negatively by the anticipated oncoming El Nino, which is reflected in my prediction made for the S2K contest.

This statement isn't true at all, the Eurosip pretty much nailed 2016-17 and actually did verify way to the cool side w/ the 2015-16 Super NINO.

[LarryWx]

I would hardly call this a substantial drop, nor would I argue we even reached +1.0 in late May, the value was closer to +0.9 than +1.0. I wouldn't over analyze every increase or fall over a 2-3 week period in upper oceanic heat content & assume it will make a huge difference in the long run, especially one this small. If this crash were to be sustained for several weeks then it would certainly make a significant difference, but remember that ENSO evolves slowly over periods of several months or more, I doubt this will really mean anything unless OHC continues to come down for another 3-4 weeks (at least). We also had more WWBs recently so it's bound to stabilize or increase again. The ocean which carries "ENSO" memory between its respective phases, evolves much more slowly than the overlying atmosphere, and it usually takes weeks for a change in atmospheric surface winds due to sub-seasonal forcing (the MJO & CCKW) to reflect onto the ocean in the large-scale. Also keep in mind the Eq Pacific still has a lot of room to play catch up the next few months and the downwelling Kelvin Wave is just now reaching the eastern boundary region (South America) and will soon refract against it, spreading anomalously warm water westward in the process (in the form of slower moving Rossby Waves).

Eric,
I agree that I would hardly call it a substantial drop and I didn't. I said "cooled a bit", meaning a small amount, rather than "substantial drop". Also, the OHC graph within the 6/4/18 report did actually show near +1.0 as per this post:
viewtopic.php?f=31&t=92137&start=9520#p2679283

CPC has since cooled it back some for that period in each of the subsequent two weekly releases, but it was showing near +1.0 then.

Regardless of semantics and exactly how much it has cooled back, it has cooled a small amount and I'm sticking with my prediction that the ASO trimonth will be warm neutral (cooler than +0.5) based largely on the May Eurosip being only warm neutral for ASO. During 2005-17 it never missed a category to the cool side. The average miss was a whopping +0.5, a very significant warm bias. I'm expecting ONI based El Nino to start during the SON trimonth or later.

What are you predicting for the ASO trimonth for Nino 3.4?

Regardless of my prediction of only warm neutral for ASO, I still expect the tropics to be affected negatively by the anticipated oncoming El Nino, which is reflected in my prediction made for the S2K contest.

You're overreacting to what's likely a very small subseasonal, or potentially unmeasurable change in the large-scale Equatorial Pacific. Also remember that the ocean is much slower to respond to the atmosphere, the supposed, apparent cooling in OHC of late is almost assuredly tied to the anomalously strong trade winds in advance of an MJO pulse that's now closing in on the Western Hemisphere, they will probably reverse and increase again because we had a fairly substantial westerly wind burst this past week, you probably won't see those changes due to this aforementioned WWB for a few or even several weeks because of the long adjustment time of the ocean.

There's also an implied, inherent error bar in the CPC's GODAS model that's used in those analyses, they differ substantially depending on the amount of data that's ingested, where the data is sampled, the model used to infill the rest of the analysis, and the resolution and data assimilation techniques for said model in addition to errors attributable to the observations themselves. A change of 0.15-0.2C in upper ocean heat content is essentially noise and shouldn't be interpreted as a significant drop that means anything in the grand scheme of things (like it will somehow stifle this event from becoming a NINO as early as ASO, especially when it occurs over a window that's comparably small vs ENSO) or even much of a drop at all.

Note the discrepancies in all the models below in their analysis of the downwelling Kelvin Wave that's crossing the Eq Pacific, do you really believe with much confidence they can detect a change of less than 0.2C in upper ocean heat content? I think not.

They're probably not too accurate. So, maybe it is better to call them estimates. But I still like to follow the OHC estimate updates for perceived trend changes. It is Eurosip that is what I had last month based my ASO prediction on. At the time, the estimated OHC was rising toward new seasonal highs. The recent slight cooldown of estimated OHC came well after that prediction, and, therefore, has nothing to do with my earlier prediction.

What are you predicting for ASO? I know you're thinking El Nino later this year, but will it occur by ASO per this ONI based table?
http://origin.cpc.ncep.noaa.gov/product ... ONI_v5.php

[Eric Webb]

I would hardly call this a substantial drop, nor would I argue we even reached +1.0 in late May, the value was closer to +0.9 than +1.0. I wouldn't over analyze every increase or fall over a 2-3 week period in upper oceanic heat content & assume it will make a huge difference in the long run, especially one this small. If this crash were to be sustained for several weeks then it would certainly make a significant difference, but remember that ENSO evolves slowly over periods of several months or more, I doubt this will really mean anything unless OHC continues to come down for another 3-4 weeks (at least). We also had more WWBs recently so it's bound to stabilize or increase again. The ocean which carries "ENSO" memory between its respective phases, evolves much more slowly than the overlying atmosphere, and it usually takes weeks for a change in atmospheric surface winds due to sub-seasonal forcing (the MJO & CCKW) to reflect onto the ocean in the large-scale. Also keep in mind the Eq Pacific still has a lot of room to play catch up the next few months and the downwelling Kelvin Wave is just now reaching the eastern boundary region (South America) and will soon refract against it, spreading anomalously warm water westward in the process (in the form of slower moving Rossby Waves).

Eric,
I agree that I would hardly call it a substantial drop and I didn't. I said "cooled a bit", meaning a small amount, rather than "substantial drop". Also, the OHC graph within the 6/4/18 report did actually show near +1.0 as per this post:
viewtopic.php?f=31&t=92137&start=9520#p2679283

CPC has since cooled it back some for that period in each of the subsequent two weekly releases, but it was showing near +1.0 then.

Regardless of semantics and exactly how much it has cooled back, it has cooled a small amount and I'm sticking with my prediction that the ASO trimonth will be warm neutral (cooler than +0.5) based largely on the May Eurosip being only warm neutral for ASO. During 2005-17 it never missed a category to the cool side. The average miss was a whopping +0.5, a very significant warm bias. I'm expecting ONI based El Nino to start during the SON trimonth or later.

What are you predicting for the ASO trimonth for Nino 3.4?

Regardless of my prediction of only warm neutral for ASO, I still expect the tropics to be affected negatively by the anticipated oncoming El Nino, which is reflected in my prediction made for the S2K contest.

This statement isn't true at all, the Eurosip pretty much nailed 2016-17 and actually did verify way to the cool side w/ the 2015-16 Super NINO.

You can also throw 2008 & 2009 into the mix, the Eurosip's ENSO forecasts were reasonable or even too cold vs reality in both instances along w/ 2015 and 2016-17.

[LarryWx]

Eric,
I agree that I would hardly call it a substantial drop and I didn't. I said "cooled a bit", meaning a small amount, rather than "substantial drop". Also, the OHC graph within the 6/4/18 report did actually show near +1.0 as per this post:
viewtopic.php?f=31&t=92137&start=9520#p2679283

CPC has since cooled it back some for that period in each of the subsequent two weekly releases, but it was showing near +1.0 then.

Regardless of semantics and exactly how much it has cooled back, it has cooled a small amount and I'm sticking with my prediction that the ASO trimonth will be warm neutral (cooler than +0.5) based largely on the May Eurosip being only warm neutral for ASO. During 2005-17 it never missed a category to the cool side. The average miss was a whopping +0.5, a very significant warm bias. I'm expecting ONI based El Nino to start during the SON trimonth or later.

What are you predicting for the ASO trimonth for Nino 3.4?

Regardless of my prediction of only warm neutral for ASO, I still expect the tropics to be affected negatively by the anticipated oncoming El Nino, which is reflected in my prediction made for the S2K contest.

This statement isn't true at all, the Eurosip pretty much nailed 2016-17 and actually did verify way to the cool side w/ the 2015-16 Super NINO.

[i mg]https://stream.ecmwf.int/data/gorax-blue-004/data/scratch_standby/8a/d0/ps2png-gorax-blue-004-b6a07f0b7be1ee2f1ad515c21ca67e14-P5mquw.png[/img]

[i mg]https://stream.ecmwf.int/data/gorax-blue-003/data/scratch_standby/d4/0e/ps2png-gorax-blue-003-b6a07f0b7be1ee2f1ad515c21ca67e14-u34nHb.png[/img]

You can also throw 2008 & 2009 into the mix, the Eurosip's ENSO forecasts were reasonable or even too cold vs reality in both instances along w/ 2015 and 2016-17.


[i mg]https://stream.ecmwf.int/data/gorax-blue-006/data/scratch_standby/e3/c6/ps2png-gorax-blue-006-b6a07f0b7be1ee2f1ad515c21ca67e14-eKnE3M.png[/img]

[i mg]https://stream.ecmwf.int/data/gorax-blue-008/data/scratch_standby/5c/f7/ps2png-gorax-blue-008-b6a07f0b7be1ee2f1ad515c21ca67e14-DxdZzP.png[/img]

Eric,
Yes, my statement is true. My statement: "During 2005-17 it never missed a category to the cool side."

Here's why:

1) I had ASO of 2015 as verifying only 0.1 too warm vs the May of 2015 ASO forecast. Since I was using the May Eurosip to make my ASO prediction. I strictly looked at past May forecasts, not June (which you're showing). It just so happens that the May of 2015 ASO forecast was warmer than the June of 2015 ASO forecast by a couple of tenths:

May of 2015 Eurosip forecast for ASO: https://stream.ecmwf.int/data/gorax-blu ... cMRk5Y.png

June of 2015 Eurosip forecast for ASO: https://stream.ecmwf.int/data/gorax-blu ... P5mquw.png

For ASO, I have May Eurosip near +2.0 and June Eurosip near +1.8

Furthermore, I'm using ONI for verification because that's what I'm trying to predict for ASO. Here's the ONI table link:

http://origin.cpc.ncep.noaa.gov/product ... ONI_v5.php

ASO of 2015 was +2.1 per this ONI table. That's why I said that the actual ASO ONI verified only 0.1 warmer than the May Eursosip ASO forecast, which was near +2.0. Note that the ONI uses ERSSTv5 data whereas those blue dotted lines of actuals on the Eurosip maps use OIv2 and came out to near +2.3 for ASO. So, there's 2 more tenths of a degree of difference.

So, if one were to analyze the June of 2015 Eurosip forecast for ASO vs the OIv2 based ASO verification as you appeared to do, you'd have Eurosip near +1.8 vs the actual of +2.3 for a miss of near 0.5 too cool. But if one were to analyze the May of 2015 Eurosip forecast for ASO vs the ERSSTv5 based verification as I did, you'd get a miss of only near 0.1 too cool meaning essentially a correct call for ASO by May.

2) I had acknowledged in my original analysis that 2009 was close with verification being only 0.2 cooler. So, May of 2009 Eurosip for ASO was too warm by 0.2. May predicted near +0.9 and it verified at +0.7 per ERSSTv5. (OIv2 had it at +0.9.)

3) The Dec. of 2008 chart you showed is irrelevant to my analysis of May Eurosip forecasts for ASO.

4) I already had acknowledged in my May 22nd post that ASO of 2015 and 2016 were nailed by the May Eurosip. Actually, I had said that May Eurosip got 5 of the 13 correct (2016, 2015, 2009, 2007, and 2006) with the other 8 clearly too warm. The average May Eurosip miss for ASO in 2005-17 was +0.5.

5) I'm still waiting for your ASO ONI prediction. Mine is warm neutral.
--------------------------------------------------------------------------------------------------------------------------

That's the end of my reply to Eric's comments. For those who want to read my 5/22/18 post that is the source of this discussion, here's the link: viewtopic.php?p=2675516#p2675516

Copy of my 5/22/18 post on the May Eurosip forecasts for ASO:

The May, 2018, Eurosip ENSO 3.4 SST anomaly forecast through October was released today:

https://stream.ecmwf.int/data/gorax-gre ... 2H4fDD.png

. I have it near +0.35 or warm neutral rather than weak El Nino for ASO averaged out. Based on what I've found to be a significant warm bias in the Eurosip, I'm now expecting no warmer than warm neutral for ASO despite a solidly warm subsurface that is now starting to rewarm slowly. Because of this warm bias and because we're still cold neutral, I can't yet count out cold neutral for ASO though I'm thinking warm neutral has the best chance right now due to the warm subsurface and since 5 of the 13 Eurosip forecasts turned out accurate. I still think it MAY get to weak to possibly low end moderate El Nino status by late fall or early winter, especially if the warm subsurface holds or warms.

I found this warm bias by looking at how the ASO 3.4 SST anomaly forecasts made in the preceding May by Eurosip verified:

Year: Eurosip's May fcast verification for ASO 3.4
2017: 1.1 cooler (cold neutral occurred vs weak El Niño prediction)
2016: 0.1 warmer (weak La Niña correctly predicted)
2015: 0.1 warmer (strong El Niño correctly predicted)
2014: 0.5 cooler (warm neutral occurred vs weak El Niño prediction)
2013: 0.5 cooler (cold neutral occurred vs warm neutral prediction)
2012: 0.9 cooler (warm neutral occurred vs moderate El Niño prediction)
2011: 1.1 cooler (moderate La Niña occurred vs warm neutral prediction)
2010: 0.9 cooler (strong La Niña occurred vs weak La Niña prediction)
2009: 0.2 cooler (weak El Niño correctly predicted)
2008: 0.8 cooler (cold neutral occurred vs weak El Niño prediction)
2007: 0.2 cooler (moderate La Niña correctly predicted)
2006: 0.2 cooler (weak El Niño correctly predicted)
2005: 0.4 cooler (cold neutral occurred vs warm neutral prediction)

So, of the 13 May forecasts for ASO, 5 were correctly predicted while 3 were one category too warm, 4 were two categories too warm, and 1 was three categories too warm. None were any categories too cold! The average was 0.5 too warm or one category too warm.

Out of the 7 Eurosip El Niño predictions for ASO in the preceding May, only 3 verified. In contrast, Eurosip predicted only 3 La Niñas in ASO but 4 occurred.

Of the 3 warm neutral predictions, 2 ended up one category too warm while 1 ended up three categories too warm. Of the 5 weak El Niño predictions, 2 ended up verifying correctly while 1 was one category too warm and 2 were two categories too warm.

Out of the 13 predictions, weak El Niño was clearly the most common prediction (5) while warm neutral was 2nd most common (3). Next was weak La Niña (2). The remainder were each predicted once: strong El Niño, moderate El Niño, and moderate La Niña. There were no cold neutral or strong La Niña predictions though 4 cold neutral occurred (the most of any category) and one strong La Niña occurred.

So, of the 13 May predictions for ASO, a whopping 10 were warmer than 0.0 while only 3 were colder. It turned out that only 5 were warmer than 0.0 while 8 were colder.

The average May Eurosip ASO 3.4 prog during 2005-17 was for +0.4 vs the -0.1 actual.

[Eric Webb]

This statement isn't true at all, the Eurosip pretty much nailed 2016-17 and actually did verify way to the cool side w/ the 2015-16 Super NINO.

[i mg]https://stream.ecmwf.int/data/gorax-blue-004/data/scratch_standby/8a/d0/ps2png-gorax-blue-004-b6a07f0b7be1ee2f1ad515c21ca67e14-P5mquw.png[/img]

[i mg]https://stream.ecmwf.int/data/gorax-blue-003/data/scratch_standby/d4/0e/ps2png-gorax-blue-003-b6a07f0b7be1ee2f1ad515c21ca67e14-u34nHb.png[/img]

You can also throw 2008 & 2009 into the mix, the Eurosip's ENSO forecasts were reasonable or even too cold vs reality in both instances along w/ 2015 and 2016-17.


[i mg]https://stream.ecmwf.int/data/gorax-blue-006/data/scratch_standby/e3/c6/ps2png-gorax-blue-006-b6a07f0b7be1ee2f1ad515c21ca67e14-eKnE3M.png[/img]

[i mg]https://stream.ecmwf.int/data/gorax-blue-008/data/scratch_standby/5c/f7/ps2png-gorax-blue-008-b6a07f0b7be1ee2f1ad515c21ca67e14-DxdZzP.png[/img]

Eric,
Yes, my statement is true. My statement: "During 2005-17 it never missed a category to the cool side."

Here's why:

1) I had ASO of 2015 as verifying only 0.1 too warm vs the May of 2015 ASO forecast. Since I was using the May Eurosip to make my ASO prediction. I strictly looked at past May forecasts, not June (which you're showing). It just so happens that the May of 2015 ASO forecast was warmer than the June of 2015 ASO forecast by a couple of tenths:

May of 2015 Eurosip forecast for ASO: https://stream.ecmwf.int/data/gorax-blu ... cMRk5Y.png

June of 2015 Eurosip forecast for ASO: https://stream.ecmwf.int/data/gorax-blu ... P5mquw.png

For ASO, I have May Eurosip near +2.0 and June Eurosip near +1.8

Furthermore, I'm using ONI for verification because that's what I'm trying to predict for ASO. Here's the ONI table link:

http://origin.cpc.ncep.noaa.gov/product ... ONI_v5.php

ASO of 2015 was +2.1 per this ONI table. That's why I said that the actual ASO ONI verified only 0.1 warmer than the May Eursosip ASO forecast, which was near +2.0. Note that the ONI uses ERSSTv5 data whereas those blue dotted lines of actuals on the Eurosip maps use OIv2 and came out to near +2.3 for ASO. So, there's 2 more tenths of a degree of difference.

So, if one were to analyze the June of 2015 Eurosip forecast for ASO vs the OIv2 based ASO verification as you appeared to do, you'd have Eurosip near +1.8 vs the actual of +2.3 for a miss of near 0.5 too cool. But if one were to analyze the May of 2015 Eurosip forecast for ASO vs the ERSSTv5 based verification as I did, you'd get a miss of only near 0.1 too cool meaning essentially a correct call for ASO by May.

2) I had acknowledged in my original analysis that 2009 was close with verification being only 0.2 cooler. So, May of 2009 Eurosip for ASO was too warm by 0.2. May predicted near +0.9 and it verified at +0.7 per ERSSTv5. (OIv2 had it at +0.9.)

3) The Dec. of 2008 chart you showed is irrelevant to my analysis of May Eurosip forecasts for ASO.

4) I already had acknowledged in my May 22nd post that ASO of 2015 and 2016 were nailed by the May Eurosip. Actually, I had said that May Eurosip got 5 of the 13 correct (2016, 2015, 2009, 2007, and 2006) with the other 8 clearly too warm. The average May Eurosip miss for ASO in 2005-17 was +0.5.

5) I'm still waiting for your ASO ONI prediction. Mine is warm neutral.
--------------------------------------------------------------------------------------------------------------------------

That's the end of my reply to Eric's comments. For those who want to read my 5/22/18 post that is the source of this discussion, here's the link: viewtopic.php?p=2675516#p2675516

Copy of my 5/22/18 post on the May Eurosip forecasts for ASO:

The May, 2018, Eurosip ENSO 3.4 SST anomaly forecast through October was released today:

https://stream.ecmwf.int/data/gorax-gre ... 2H4fDD.png

. I have it near +0.35 or warm neutral rather than weak El Nino for ASO averaged out. Based on what I've found to be a significant warm bias in the Eurosip, I'm now expecting no warmer than warm neutral for ASO despite a solidly warm subsurface that is now starting to rewarm slowly. Because of this warm bias and because we're still cold neutral, I can't yet count out cold neutral for ASO though I'm thinking warm neutral has the best chance right now due to the warm subsurface and since 5 of the 13 Eurosip forecasts turned out accurate. I still think it MAY get to weak to possibly low end moderate El Nino status by late fall or early winter, especially if the warm subsurface holds or warms.

I found this warm bias by looking at how the ASO 3.4 SST anomaly forecasts made in the preceding May by Eurosip verified:

Year: Eurosip's May fcast verification for ASO 3.4
2017: 1.1 cooler (cold neutral occurred vs weak El Niño prediction)
2016: 0.1 warmer (weak La Niña correctly predicted)
2015: 0.1 warmer (strong El Niño correctly predicted)
2014: 0.5 cooler (warm neutral occurred vs weak El Niño prediction)
2013: 0.5 cooler (cold neutral occurred vs warm neutral prediction)
2012: 0.9 cooler (warm neutral occurred vs moderate El Niño prediction)
2011: 1.1 cooler (moderate La Niña occurred vs warm neutral prediction)
2010: 0.9 cooler (strong La Niña occurred vs weak La Niña prediction)
2009: 0.2 cooler (weak El Niño correctly predicted)
2008: 0.8 cooler (cold neutral occurred vs weak El Niño prediction)
2007: 0.2 cooler (moderate La Niña correctly predicted)
2006: 0.2 cooler (weak El Niño correctly predicted)
2005: 0.4 cooler (cold neutral occurred vs warm neutral prediction)

So, of the 13 May forecasts for ASO, 5 were correctly predicted while 3 were one category too warm, 4 were two categories too warm, and 1 was three categories too warm. None were any categories too cold! The average was 0.5 too warm or one category too warm.

Out of the 7 Eurosip El Niño predictions for ASO in the preceding May, only 3 verified. In contrast, Eurosip predicted only 3 La Niñas in ASO but 4 occurred.

Of the 3 warm neutral predictions, 2 ended up one category too warm while 1 ended up three categories too warm. Of the 5 weak El Niño predictions, 2 ended up verifying correctly while 1 was one category too warm and 2 were two categories too warm.

Out of the 13 predictions, weak El Niño was clearly the most common prediction (5) while warm neutral was 2nd most common (3). Next was weak La Niña (2). The remainder were each predicted once: strong El Niño, moderate El Niño, and moderate La Niña. There were no cold neutral or strong La Niña predictions though 4 cold neutral occurred (the most of any category) and one strong La Niña occurred.

So, of the 13 May predictions for ASO, a whopping 10 were warmer than 0.0 while only 3 were colder. It turned out that only 5 were warmer than 0.0 while 8 were colder.

The average May Eurosip ASO 3.4 prog during 2005-17 was for +0.4 vs the -0.1 actual.

You never specified if this verification was against the peak of the ENSO event or a particular tri-monthly period & correct me if I'm wrong but some of those Eurosip forecasts were fairly realistic or generally too cold even in general.

Let me instill some wisdom upon you, over analyzing every minute statistic about the Eurosip forecast as you've done here is truly pointless, putting all or most of your chips into one or just a couple factors for a particular time stamp and trying to get an extremely specific answer that really isn't going to make a difference in the large-scale will often come back to bite you. It doesn't really matter if this NINO "officially" develops in ASO or SON, and is +0.4C, 0.5C, or +0.6C by then. There's no magical all-inclusive, end all-be all definition of ENSO wrt SSTAs, the CPC's is far from perfect in its own right (& I'm not the biggest fan of it personally) and often misses some weak events (as you can see in my ENS ONI index), using a collection of definitions and the large-scale pattern is moving towards NINO conditions and will be there generally speaking by the equinox give or take a month or so. The low frequency background state will already be heading in that direction well before ASO as a standing atmospheric wave develops over the Western Hemisphere, a classic pattern evident in NINOs (there's also enhancement by interdecadal variability w/ the ascending branch of the Hadley Cell over Africa and the far western IO gaining prowess relative to the rest of the globe)

 https://twitter.com/MJVentrice/status/1009187292232192002




We've been tracking just on the lower side of the distribution of most weak-moderate El Ninos that develop by the equinox since the mid 19th century (1880-81, 1884-85, 1911-12, 1923-24, 1925-26, 1929-30, 1976-77, 1986-87, 1994-95, & 2014-15 (1884-85 may have developed in the spring, ENS ONI could be over damped here & it's also possible there was an El Nino in 1883-84, some reconstructions differ in this regard). Depending on if you use the CPC definition of +0.5C for 5 successive tri-monthlies, Trenberth and Hoar (1997) definition that I use in my ENS ONI (+0.4C for 6 successive tri-monthlies), or want to follow the Reid (2003) of half standard deviation (or greater) SSTAs, or even the JMA's definition of 6 successive pentads greater than 0.5C, you may end up w/ a very different answer with the ENSO threshold being met in SON or ASO but you also shouldn't focus all of your attention on when this precisely happens or even on one definition of ENSO because it really won't matter a lot in the end. They all have their drawbacks and even if they were somehow perfect, NINO 3.4 region SSTs, despite being in the highest loading areas for ENSO, actually doesn't capture all of ENSO's variance and may over-represent northern hemisphere near-equatorial SSTs.

Yeah you heard that right, there's actually some non-negligible asymmetry in ENSO's expression of near-equatorial SSTs, the "center of mass" of the SSTAs in the Equatorial Pacific is not on the equator, it actually leans slightly into the southern hemisphere! Conventional indices like the ONI or SOI won't account for that or even how ENSO evolves according to the seasons (but EOF analysis will to some extent). Most El Nino events begin in the the east-central equatorial Pacific and fade westward w/ time, becoming more modoki-like as they age. The Southern Oscillation SLP dipole is also stronger in the boreal winter than the summer because the ITCZ shifts northward to the warmer hemisphere and isn't centered over Darwin and Tahiti.

November-March (1950-2017) Equatorial Pacific NINO 3.4 SST correlation.


As was true with the CPC's GODAS model analysis of integrated oceanic heat content, there's also inherent error in the SST analyses (John Kennedy has lots of great material on this particular topic.) For one, we can't measure every point on the earth at every possible time stamp, filling in the missing points leads to errors (on the order a few tenths of a degree C depending on the analysis), the preferred resolution, how you reconstruct these points (either via satellites, optimum interpolation, optimal smooth, EOF reconstruction, or all the above (just to include a few), the satellite radiance bands are also hindered by cloud cover and can be noisy, if you use a reanalysis model, there's error we simply can't account for and don't understand and is attributable to each model's data assimilation system, and of course let's not forget there's error in the observations themselves! Even if you were somehow able to account for all the above, you would also have to consider that in the base periods that best represent this ENSO event will change in the future decade or two because as the globe continues to warm and/or our observational platforms change, 1991-2020 and then 2001-2030 will actually afford a better estimate of this event's intensity, and those could differ from 1981-2010 by a few tenths of a degree centigrade and it's possible that this El Nino (even if it's classified later this year) may not exist altogether if the climate warms enough in the 2020s and is too close to the NINO threshold!

Asking for precisely when the Equatorial Pacific will cross this particular CPC threshold w/ ERSSTv5 which they use in their ONI tables & quite frankly doesn't handle modern ENSO events too well, (a lot of its data in the quality control stage of constructing the ENS ONI was flagged), is honestly futile. It's really not going to matter whether we officially meet NINO conditions in ASO or SON, the sensible impacts would virtually be the same on the Atlantic Hurricane Season and forthcoming winter assuming it persists. Let's also keep in mind this is not by any means the only scenario, this NINO may not develop at all, or since the negative feedbacks are usually pretty modest w/ weak-moderate NINOs, we could be setting the stage for an even larger event later in 2019.

[cycloneye]

@philklotzbach
Average of dynamical model guidance (red line) has slowly trended warmer over the past few months and is now calling for borderline weak #ElNino event by peak of Atlantic #hurricane season (August-October).

 https://twitter.com/philklotzbach/status/1009110942007742464

[Eric Webb]

 https://twitter.com/webberweather/status/1009392304971501568

[NotSparta]

https://twitter.com/webberweather/statu ... 4971501568

Yep, the +PMM causing El Niño like conditions over the MDR as you said

[Eric Webb]

https://twitter.com/webberweather/statu ... 4971501568

Yep, the +PMM causing El Niño like conditions over the MDR as you said

Yep, and a huge key here is the Atlantic is cold. If the Atlantic was warm not only would it attempt to resist an oncoming El Nino, thwart the EP (although it's not always successful at this), a warmer Atlantic also impacts its own shear locally. Remember that wind shear is created due to the thermal wind (i.e. temperature gradients and baroclinicity). When the Atlantic is warmer, convection is more readily generated and the large-scale environment becomes increasingly barotropic, because a warmer sea surface steepens low-mid level lapse rates that make the atmosphere generally more unstable. Convection in essence heats the mid-upper troposphere, causing heights and pressures to rise, providing forcing for a local anticyclone over the MDR that resists the upper level westerly shear induced by the +PMM and/or active EP.

If you were to compare 2 sets of +PMM years that didn't observe an El Nino, those with a colder Atlantic actually have more shear in the MDR than years where the MDR is warm. Although the anomaly difference isn't anywhere near as significant as ENSO (about 3-4x weaker in magnitude), it should not be ignored particularly in years where the ENSO signal is modest at best.

[NotSparta]

https://twitter.com/webberweather/statu ... 4971501568

Yep, the +PMM causing El Niño like conditions over the MDR as you said

Yep, and a huge key here is the Atlantic is cold. If the Atlantic was warm not only would it attempt to resist an oncoming El Nino, thwart the EP (although it's not always successful at this), a warmer Atlantic also impacts its own shear locally. Remember that wind shear is created due to the thermal wind (i.e. temperature gradients and baroclinicity). When the Atlantic is warmer, convection is more readily generated and the large-scale environment becomes increasingly barotropic, because a warmer sea surface steepens low-mid level lapse rates that make the atmosphere generally more unstable. Convection in essence heats the mid-upper troposphere, causing heights and pressures to rise, providing forcing for a local anticyclone over the MDR that resists the upper level westerly shear induced by the +PMM and/or active EP.

If you were to compare 2 sets of +PMM years that didn't observe an El Nino, those with a colder Atlantic actually have more shear in the MDR than years where the MDR is warm. Although the anomaly difference isn't anywhere near as significant as ENSO (about 3-4x weaker in magnitude), it should not be ignored particularly in years where the ENSO signal is modest at best.

In addition to this, a cooler MDR commonly means a stronger subtropical high, causing stronger trades. This in turn increases westerly shear without any help from the EP or any other external forcing. Of course, though, most of the effect is caused by how barotropic the environment is.

[Eric Webb]

Yep, the +PMM causing El Niño like conditions over the MDR as you said

Yep, and a huge key here is the Atlantic is cold. If the Atlantic was warm not only would it attempt to resist an oncoming El Nino, thwart the EP (although it's not always successful at this), a warmer Atlantic also impacts its own shear locally. Remember that wind shear is created due to the thermal wind (i.e. temperature gradients and baroclinicity). When the Atlantic is warmer, convection is more readily generated and the large-scale environment becomes increasingly barotropic, because a warmer sea surface steepens low-mid level lapse rates that make the atmosphere generally more unstable. Convection in essence heats the mid-upper troposphere, causing heights and pressures to rise, providing forcing for a local anticyclone over the MDR that resists the upper level westerly shear induced by the +PMM and/or active EP.

If you were to compare 2 sets of +PMM years that didn't observe an El Nino, those with a colder Atlantic actually have more shear in the MDR than years where the MDR is warm. Although the anomaly difference isn't anywhere near as significant as ENSO (about 3-4x weaker in magnitude), it should not be ignored particularly in years where the ENSO signal is modest at best.

In addition to this, a cooler MDR commonly means a stronger subtropical high, causing stronger trades. This in turn increases westerly shear without any help from the EP or any other external forcing. Of course, though, most of the effect is caused by how barotropic the environment is.

I'd certainly contend that the impact from stronger easterly trades is pretty significant and is as important as upper level forcing. Remember that shear is measured by the vector difference between the low-level and upper level winds (usually the 850 hPa & 200 hPa levels). You could have near average upper level westerly winds but stronger than average low-level easterlies (as is often true in a cold AMO) and that would still result in above normal deep layer westerly wind shear even if TUTT intrusions into the MDR were near normal. Many often focus almost all of their attention on upper level westerly winds (via TUTTs for ex) to determine deep layer shear and associate strong easterly trades w/ cooling of the sea surface via mixing but they tend to overlook the impact the low-level trades have on the deep layer wind shear, and they still matter a lot actually.

[Eric Webb]

Intraseasonal forcing will back off the gas pedal temporarily in July but the EPS weeklies shows the atmosphere clearly moving to a NINO state next month w/ upward motion focused over the east-central Pacific and an intriguing area of secondary upward motion over Africa. The Atlantic likely won't be favorable enough to take advantage of this whatsoever but the Northeastern Pacific will love it. This large-scale pattern is arguably even more favorable for the East Pacific than the last active era during the 1980s and 1990s w/ an active AEW train. A large proportion of East Pacific tropical cyclones owe their origins not only to in-situ development off the high terrain of Central America but to a lesser extent, African Easterly Waves. NWP simulations have shown that while the contribution from AEWs is less than in-situ development off of Central America or within the EP ITCZ, loss of AEWs resulted in a noticeable decrease in EP TCG events. What we're seeing atm with NINO forcing, a +PMM, -AMO, and an active AEW train is about as favorable of a seasonal pattern that could be possibly dealt to the NE Pacific basin.

 https://twitter.com/RyanMaue/status/1009476865608822784